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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Studies on ornithine-[delta]-transaminase in rat liver and hepatoma

Park, Hyun Suh, January 1969 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
12

Neurohumoral regulation of adrenal ornithine decarboxylase activity

Alamzàn, Guillermina January 1982 (has links)
No description available.
13

Attempted routes towards the synthesis of fluorinated analogues of ornithine as potential inhibitors of ornithine decarboxylase

De Villiers, Jandre 03 1900 (has links)
Thesis (MSc (Chemistry and Polymer Science))--University of Stellenbosch, 2007. / Human African Trypanosomiasis (HAT) is a disease that threatens more then 60 million men, woman and children in Africa. It is known that the inhibition of the enzyme, ornithine decarboxylase (ODC) leads to cell arrest and subsequent death of Trypanosoma brucei, the parasite that causes the disease. The fluorinated ornithine analogue, DFMO (difluoromethylornithine or eflornithine) is a known inhibitor of ODC. Although various syntheses for DFMO exist they have some practical drawbacks which prevent the cost effective production of this compound as a drug for HAT treatment. This work focuses on the synthetic preparation of the fluorinated ornithine analogue DFMO as well as the fluorinated ornithine analogues 2-MFMO, 3-fluoro-ornithine and 3,3-difluoro-ornithine. Our chosen synthetic methodology focused on the introduction of the fluorine functionality using a simpler, safer and more convenient method than current direct fluorination techniques, or those that rely on the use of CFCs. Instead we decided to develop and optimise a fluorodehydroxylation method based on the transformation of hydroxylated ornithine analogues. The fluorodehydroxylation method substitutes a hydroxyl group to the corresponding fluorine and can also be used to transform an aldehyde or ketone to the corresponding difluoro group. Application of this fluorination method requires the synthesis of appropriate ...
14

Amino acid sequence requirements for ornithine decarboxylase activity

Chu, Yi-wen, 1962- January 1988 (has links)
ODC activity of the altered proteins was measured and compared to that of the full length 461 amino acid containing ODC. Mouse ODC cDNA sequences were deleted from either 5' or 3' ends using exonuclease III and Mung Bean nuclease treatments. An internal deletion was obtained by Hinc II and Bcl I restriction endonuclease digestion of the full length ODC cDNA. Capped mRNAs were synthesized in vitro using the resulting deleted DNA as templates, and the protein was translated in vitro. The results indicate that the protein in which translation initiates at internal AUG start codons does not have any activity. The protein with 39 amino acids deleted from carboxy-terminus maintains 12% of the activity, while deletion of greater than 79 amino acids have no activity. An internal deletion from amino acid 290 to 331 and which may contain the suspected ornithine binding site has no activity. These results suggest that the entire amino acid sequence of mouse ODC is required for full activity of the enzyme.
15

The role of polyamines in cellular and molecular events in the wool follicle

Nancarrow, Michelle Jane. January 1995 (has links) (PDF)
Bibliography: leaves 255-280. In vivo and in vitro investigations of the hypothesis that polyamines and their synthetic enzymes have a role in regulation of cellular and molecular processes in the follicle. The activity of ornithine decarboxylase (ODC), the rate limiting polyamine biosynthetic enzyme, is demonstrated in wool follicle homogenates.
16

Phosphoenolpyruvate carboxykinase and ornithine decarboxylase genes : allelic variations and associations with traits in poultry

Parsanejad, Reza January 2003 (has links)
The objectives of this study were to identify genetic variants, develop the respective haplotypes (combination of alleles) and investigate the association of identified variants with economically important traits in two candidate genes. The first gene was Phosphoenolpyruvate carboxykinase (PEPCK) which is a key regulatory enzyme of gluconeogenesis. The second candidate gene, Ornithine decarboxylase (ODC), is a rate-limiting enzyme in polyamine biosynthesis. It has a significant role in DNA synthesis and cell proliferation. We first analyzed the genetic variability of PEPCK-C, the gene which codes for the cytosolic form of PEPCK. A 3792 by segment of 5'-region of the PEPCK-C gene (pos. -1723 to 2069) was sequenced in 32 White Leghorn chickens (a total of 64 genomes). A total of 19 single nucleotide polymorphisms (SNPs) were identified. We then analyzed the genetic variability of ODC. A 5 kb sequence of 3' end of the gene was sequenced in 20 White Leghorn chickens (a total of 40 genomes). A total of 63 variant sites were identified. The rate of insertion/deletion in ODC was 16%, whereas neither deletions nor insertions were present in PEPCK-C. Gene trees were constructed for both genes assuming maximal parsimony. This led to the delineation of 6 haplotypes in PEPCK-C. Two of the SNPs coincided with RFLP detectable by the restriction enzymes AciI and BstEII, respectively. Three haplotypes in ODC were defined. In the next step, White Leghorn chickens from a non-selected closed population were typed for these two PEPCK-C RFLP. The two RFLP gave rise to three alleles (or haplotype classes), which in turn defined six genotypes. A comparison of genotypes revealed significant differences in feed efficiency (FE) and residual feed consumption (RFC). There was significant interaction between PEPCK-C genotypes and mitochondrial PEPCK (PEPCK-M) genotypes defined by an RFLP. The latter enzyme catalyzes the same reaction, but is located in the matrix of t
17

The role of the 5 ́untranslated region in gene expression of ornithine aminotransferase

MacDonald, Heather R. (Heather Ruth) January 1995 (has links)
Ornithine-$ delta$-biaminotransferase (OAT) is a mitochondrial matrix a enzyme which catalyzes the reversible conversion of ornithine to glutamic semialdehyde. In the retinoblastoma cell line Y79, the 5$ sp prime$ UTR of the OAT mRNA is alternatively-spliced. Previous work has shown that the two alternatively-spliced 5$ sp prime$ UTR are translated with different efficiencies. / The alternatively-spliced 5$ sp prime$ UTRs were isolated and subcloned. Expression vectors were constructed containing each of the OAT 5$ sp prime$ UTRs and the human growth hormone as a reporter gene. Transient transfection expression analysis in COS-1 cells confirmed that the 5$ sp prime$ UTRs conferred differential expression on the reporter gene. The shorter 5$ sp prime$ UTR was expressed at a level 3-fold higher than that of the longer 5$ sp prime$ UTR. / RNA mobility shift assays were performed to determine whether a transacting factor was interacting with one of the alternatively-spliced 5$ sp prime$ UTRs. A binding activity was detected that bound to the longer, exon 2-containing 5$ sp prime$ UTR with a significantly higher affinity than the shorter 5$ sp prime$ UTR. Competition studies demonstrated that this binding activity was specific for the longer 5$ sp prime$ UTR.
18

The role of polyamines in cellular and molecular events in the wool follicle / by Michelle Jane Nancarrow.

Nancarrow, Michelle Jane January 1995 (has links)
Includes bibliographical references (leaves 255-280) / xv, 280 leaves, [24] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / In vivo and in vitro investigations of the hypothesis that polyamines and their synthetic enzymes have a role in regulation of cellular and molecular processes in the follicle. The activity of ornithine decarboxylase (ODC), the rate limiting polyamine biosynthetic enzyme, is demonstrated in wool follicle homogenates. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 1995
19

The role of calcium in control of animal cell proliferation : ornithine decarboxylase induction by L-asparagine in Reuber H-35 hepatoma cell

Pong, Nga Hin 01 January 1991 (has links)
No description available.
20

Phosphoenolpyruvate carboxykinase and ornithine decarboxylase genes : allelic variations and associations with traits in poultry

Parsanejad, Reza January 2003 (has links)
No description available.

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